A portable miracle machine that breathes life into ailing livers outside the body could revolutionise organ transplants, experts believe.

The device, set on wheels and the size of a supermarket trolley, can keep a donor liver alive for 24 hours or more at body temperature.

As well as preserving the organ, it helps damaged tissue repair itself by delivering a carefully balanced combination of blood, oxygen and nutrients.

Doctors believe the machine, which could be ready to market in Europe next year, has the potential to double the number of livers available for transplant.

In five years it could replace the current method of flushing an organ with preservative, cooling it to 4C and racing to carry out the transplant before deterioration sets in.

Modified versions of the device may also assist transplants of other organs, including kidneys and lungs, and provide a tool for testing the toxicity of new medicines.

Trial

Two patients are said to be recovering well after taking part in a pilot trial to test the machine at London's King's College Hospital, Europe's biggest organ transplant centre.

Ian Christie (62) from Devon, the first person in the world to benefit from the technology, said: "I feel better than I've felt for 10 to 15 years, even allowing for the pain and wound that's got to heal. I'm getting better and better day by day."

Another female liver recipient has also delighted surgeons with her progress. Neither patient has suffered any complications.

To operate the machine, surgeons simply place the donor liver into a holding container, plug in tubes carrying blood and bile, and press a "start" button. The device then runs itself automatically, supplying the tissue with the right balance of oxygen and nutrients.

In the pilot trial, the device was used to preserve donor livers for just 10 hours. But experts from the Oxford University design team are confident they can keep organs functioning outside the human body for 24 hours.

Using the standard cooling technique, an "ideal" liver can be stored for a maximum of 20 hours, but in practice most surgeons dare not wait longer than 14. Every hour that passes causes the organ to suffer some degree of irreparable damage.

Professor Constantin Coussios, co-inventor of the machine, said: "It was astounding to see an initially cold grey liver flushing with colour once hooked up to our machine."